Modified nonlinear pressure estimator of pneumatic actuator for force controller design

Abstract

This paper presents a modified nonlinear pneumatic model for pneumatic force servo systems. The modified model is proposed in order to estimate pressures accurately for both chambers of a pneumatic cylinder by adopting flow coefficient maps, which is different from a conventional model whose flow coefficient is constant. The simulated data from the model is also compared to the experiment result and shows its accuracy compared to a widely used conventional model. The modified model and the experimental procedure are described and verified in this paper as well. Finally, the applicability of the proposed model to model-based controller design is also shown through the experiment of force servo controls based on a force sensor.